engine dying at idle

[Murphy]

lately my Legacy has got into the habit of dying at stoplights, today i pulled up by a Mustang at a light that had passed me pretty fast back down the road, then his car stalled so i just started laughing pretty good. so the light turns green, he starts up and leaves, i go to take off and my car dies . it stared up quickly like normal though so i floored it (not on purpose) and spun my front wheels all through the intersection

it does that at probably 1 out of every 10 stoplights, its a random thing so im never paying attention to whats hapening when it dies, but it does idle pretty low sometimes, it does it when im sitting in the driveway to, the motor will idle at about 1000rpms, i tap the gas and it revs and comes down to under 800rpms, if it sits long enough it will die

could this just be a problem with the idle controller

[Legacy777]

Could be an issue with the IAC valve.....or even the MAF sensor....there's several recent threads referring to MAF sensor issues.

[Murphy]

whats the IAC valve, were can i find it?